Invasive annual grasses have been pushing aside native perennials in California for the last 200 years. An Agricultural Research Service (ARS) scientist, along with university and environmental collaborators, is trying to reverse the trend and thus improve forage quality while helping the environment.
Plant pathologist Stephen M. Griffith of the ARS Forage Seed and Cereal Research Unit, Corvallis, Ore., is studying how revegetation of desirable perennial grasses affects soil and water quality and whether it supplies quality grazing forage.
Perennial grasses turn green faster, stay green longer and produce more biomass, making a higher-quality forage for wildlife and livestock than annual grasses. The perennial grasses also improve biodiversity and other environmental qualities.
Only 2 percent of California's grasslands are covered predominately by perennial grasses. Griffith is working with Audubon California to establish perennials in areas where annual grasses dominate. Early results indicate it can be difficult at first to establish native grasses, but once they are fully established, their deep roots may be expected to outcompete the annual grasses.
Ranchers who Griffith works with already appreciate the benefits of the native grasses. Griffith hopes that showing these benefits will lead to increased and more predictable demand, encouraging greater seed production and lower prices. For while turf grass seed sells for as little as 50 cents a pound, perennial grass seed currently costs as much as $40 a pound.
Griffith's collaborators are looking at which plants, in addition to grasses, make up a healthy grassland, what kinds of wildlife appear after native grasses are reintroduced, and what the biomass of grasslands is.
More information about this research can be found in the May issue of Agricultural Research magazine, available online at: http://www.ars.usda.gov/is/AR/archive/may04/grass0504.htm